"Our study confirmed that Dysport (abobotulinumtoxinA) is a safe and effective tool in fighting wrinkles," said Dr. Rod Rohrich, chairman of plastic surgery at UT Southwestern Medical Center and one of the study's authors.
"It also confirmed that the dosage should be tailored to one's facial muscle mass to be most effective. So it's important to visit with a certified plastic surgeon to ensure the dosage is correct," Rohrich added.
The Food and Drug Administration-approved study involved 816 participants with moderate to severe frown lines (called glabellar lines) at 27 centers in the U.S.
Study participants, who kept diaries for the first 14 days after being injected, were given the Dysport facial filler or a placebo.
Surgeons injected Dysport in various levels, dependent on sex and facial mass, at five facial points.
Self-assessments and assessments by independent reviewers were performed six times over a five-month follow-up period.
87 percent of people given Dysport reported a reduction in wrinkles, compared with 5 percent of patients taking placebos who reported an improvement.
An independent assessment showed improvement among 85 percent of patients receiving Dysport, compared with 3 percent of patients receiving the placebo.
The study also confirmed that dosing should be adjusted according to a person's facial muscle mass.
"Most studies have evaluated Dysport with a standard dosage. This study evaluated the safety and effectiveness of different doses based on a person's specific muscle mass, which better mirrors what occurs in clinical practice. The size and use of the muscles that produce frown lines varies among individuals, so you want to customize treatment to the patient's face," Rohrich said.
The study is available online and will appear in Plastic and Reconstructive Surgery.